Abstract

This study was conducted to identify sheep breeding objectives, existing breeding strategies and selection criteria in mixed crop-livestock, agro-pastoral
and pastoral production systems in eastern Ethiopia. A preliminary survey, group discussion and a detailed structured questionnaire were used to collect
data from 270 households (90 from each production system). Based on an index, the overall primary objective for sheep production in eastern Ethiopia was
income generation (0.38) followed by milk production (0.26) and meat production (0.13), but with different ranking order and index value among the
production systems. Thus, milk production was the primary objective of sheep production in pastoral and agro-pastoral systems but this was not common in
the mixed crop-livestock farming. Birth (0.64) and sale (0.47) of sheep were the major means of acquisition and mode of disposal, respectively, across all
the production systems. Controlled breeding was practiced to match lambing season with feed availability in pastoral production system; uncontrolled
breeding was more common in the others. In all production systems, overall appearance, fast growth and coat color were the most preferred attributes in
selection of rams for breeding. For ewes, overall appearance and traits related to mothering ability were preferred. Adaptive traits such as tail type
(0.16) and adaptation (0.17) to heat stress and feed scarcity were given greater emphasis in the pastoral production system compared to agro-pastoral and
mixed crop-livestock systems.

Difference in production objectives, trait preference of the sheep owners and breeding practices among production systems needs to be considered in
designing sustainable breeding strategy to improve productivity of sheep in the study area.

Introduction

Small ruminants (sheep and goats) have a unique niche in smallholder agriculture from the fact that they require small investments; have shorter production
cycles, faster growth rates and greater environmental adaptability as compared to large ruminants. They are important protein sources in the diets of the
poor and help to provide extra income and support survival for many farmers in the tropics and sub-tropics (Tibbo et al 2006; Notter 2012).

In Ethiopia, sheep are the second most important livestock species next to cattle with nine diverse breeds (Gizaw et al 2007) which have become adapted to
a range of environments from the cool alpine climate of the mountains to the hot and arid pastoral areas of the lowlands (Mirkana 2010). There are about
24.2 million sheep in Ethiopia, out of which 99.7% is indigenous breeds (CSA 2012). Sheep play an important economic role and make a significant
contribution to both domestic and export markets through provision of food (meat and milk) and non-food (manure, skin and wool) products. They also play a
major role in the food security and social well-being of rural populations living under conditions of extreme poverty which is particularly the case for
eastern parts of Ethiopia (Alvarez et al 2009; Duguma et al2010).

The demand from both domestic and export markets for product from small ruminants, especially mutton, is increasing in Ethiopia (SPS-LMM 2010). The
productivity of indigenous sheep is currently too low to meet this demand (Sebsibe 2008). Attempts have been made to improve productivity of indigenous
sheep through crossing with exotic breeds such as Corriedeale, Hampshire, Romney, Awassi and Dorper (Gizaw and Getachew, 2009). However, these programs
have not been successful, probably because of a lack of understanding of the preferred breeding objectives of the farmers and absence of involvement of all
stakeholders in the designing of breeding strategies (Tibbo et al 2006, Duguma et al 2010). While previous studies have identified breeding objectives and
breeding practices associated with the rearing of indigenous sheep in Ethiopia (Getachew et al 2010; Getachew et al 2011; Edea et al 2012), the diversity
of production systems and genetic resources is still not well-represented. In particular, there is limited information on breeding practices, trait
preferences, and selection criteria of breeding stock used by owners of sheep in eastern parts of the country where indigenous breeds have special merit in
Middle Eastern export markets (SPS-LMM 2010).

Understanding the purposes of keeping sheep and the functional basis of traditional breeding practices is a prerequisite for designing sustainable sheep
genetic improvement programs and strategies for the future development of indigenous breeds.

Objective

To identify breeding objectives, existed breeding strategies and selection criteria of sheep owners in different production systems in Eastern Ethiopia.

Materials and Methods

Study areas

The study was conducted in Eastern Ethiopia in Jijiga and Shinile (Somali National Regional State), and eastern Hararghe (Oromia National Regional State)
zones.

Jijiga zone is located at about 620 km south-east of Addis Ababa at 4o-11o N Latitude and 40o- 48o E Longitude. Its altitude ranges from
500 to 1,600 m.a.s.l. The temperature ranges from 16 to 20ºC. It has a bimodal pattern of rainfall (March to May; July to mid October); with annual
rainfall ranges 600 to 700 mm (NMSA 2004). The total domestic livestock population in Jijiga zone is estimated to be about 1.8 million, of which 44.5% are
sheep (CSA 2012). Agro-pastoralism is the dominant production system in this zone.

Shinile zone is located 460 km south-east of Addis Ababa and 179 km northwest of Jijiga (capital city of SNRS) at 9o-10o N Latitude
and 41o-42o E Longitude. Its altitude ranges from 950 to 1350 m.a.s.l. The temperature ranges from 28 to 38 ºC. The rainfall pattern
of the area is bimodal similar to Jijiga zone, and the annual rainfall ranges from 300-600 mm. The total livestock population in the zone is estimated to
be about 0.29 million, of which 17.7% are sheep (CSA 2012). Pastoralism is the predominant production system in the zone.

Eastern Harerghe zone is located 518 km south-east of Addis Ababa at 8o-9o N Latitude and 40o-42o E Longitude.
Its altitude ranges from 500 to 3405 m.a.s.l. The mean annual temperature varies between 13ºC to 28ºC. The mean annual rainfall ranges from 400-1200 mm.
The zone receives bimodal type of rainfall pattern, which covers from June to September (main season), and from April to May (short season). The total
livestock population in the zone is estimated to be 2.7 million of which 14.3% is sheep (CSA 2012). A mixed crop-livestock system is the predominant
production system in this zone.

Sampling method and data collection

Jijiga, Shinile and eastern Haraghe zones were selected based on sheep distribution and production system, and agro ecologies. The Rapid Rural Appraisal
(RRA) technique (Ibrahim and Olaloku 2000) was used to identify sampling areas. Group discussions were held with experts working at Zonal and District
levels, with elders representing the study areas and all the production systems, and other key informants. These discussions were used to obtain
appropriate information about sheep distribution, their origin and traditional classification before commencement of the actual survey.

Stratified purposive sampling was employed to select districts and rural localities (Kebeles) from each zone based on distribution of sheep
population, production system and accessibility. Three production systems were identified in the area: mixed crop-livestock, agro-pastoral and pastoral.
Thus, a total of nine districts (3 from each production system) and 18 rural Kebeles (2 from each district) were selected for the study. The total
number of households selected for the study was 270 (90 from each production system). Simple random sampling was used to select target respondents.

Semi-structured questionnaires and formal interviews were used to gather information from the selected households. Data on purpose of keeping sheep, ways
of acquisition and disposal from the farm, breeding practices and selection criteria used for breeding rams and ewes were collected by trained enumerators.
The questionnaire was tested before the actual survey to ensure that all questions were of sufficient clarity for the interviewees. Group discussions were
also made with elders, sheep owners and Development Agents (DAs) across all the production systems during the actual survey. Such discussions were also
used to validate information collected from the individual farmers.

The rate of inbreeding coefficient (ΔF) was calculated from effective population size (Ne) as ΔF = 1/2Ne. The Ne for a
randomly mated population was calculated as Ne = (4Nm Nf) / (Nm + Nf) (Falconer and Mackay, 1996),
where, Ne = effective population size, Nm = number of breeding males and Nf = number of breeding females.

Statistical data analysis

Statistical Package for Social Sciences (SPSS 16.0 2007) was used to analyze the data. Descriptive statistics were used to describe the results as
percentages for all production systems. Microsoft Excel 2007 was used for ranking of data on reasons for keeping sheep, and sheep acquisition and disposal,
the ranking being expressed as an Index = Sum of (3 for rank 1 + 2 for rank 2 + 1 for rank 3) given for an individual reason divided by the sum of (3 for
rank 1 + 2 for rank 2 + 1 for rank 3) for all reasons (Kosgey 2004). Similar indexes were calculated for ranking selection criteria associated with
breeding both females and males.

Result and Discussion

Purposes of keeping sheep

The primary objective for keeping sheep in eastern Ethiopia was income generation (0.38) followed by milk (0.26) and meat (0.13) production (Table 1).
While the indices for other purposes were small, manure production for fertilizing cropping land (0.04) was of some importance in the mixed crop-livestock
system, and dowry in agro-pastoral (0.01) and pastoral (0.02) systems. Index value and rank order differed between the production systems. Milk production
was the primary objective in agro-pastoral (0.40) and pastoral (0.36) production systems followed by income generation (0.35 and 0.28, respectively). In
the mixed crop-livestock system, income generation (0.52) was the primary objective followed by meat production (0.18) and wealth accumulation (0.13).
Group discussion revealed that production and consumption of milk were common and contributes to livelihood in the study areas, especially when goat and
camel milk were not available. Getachew et al (2010) also reported that milk production from sheep was the primary objective of pastoralists in north-east
Ethiopia (Afar), respectively. However, Urgessa et al (2012) and Edeaet al (2012) reported that production and consumption of milk from sheep is
not common in mixed crop-livestock system where income generation is considered as the primary objective of keeping sheep.

Although the primary purposes differed between production systems, the use of indigenous sheep as multipurpose animals was common to all production
systems. Multi-purpose sheep rearing is common in Ethiopia (Getachew et al 2010; Gizaw et al 2010; Edea et al 2012) and linked to the need to maximize
output from an animal that can survive on a low input of resources (Jimmy et al 2010). Multiple functions are particularly important in low- to
medium-input production environments (Edea et al 2012). Given the breadth of purposes that farmers and pastoralists have for keeping sheep, much care is
required in the choice of breeding objectives and breeding strategies as the function of the animals is closely linked to the traits desired by the
producers (Jimmy et al 2010). Knowledge of reasons for keeping animals is a prerequisite for deriving operational breeding goals (Jaitner et al 2001). Milk
production of sheep should always be considered in designing a breeding strategy for pastoral and agro-pastoral systems where sheep milk consumption is
common and acceptable.

Table 1: Reasons for keeping sheep as ranked by respondents in different livestock production systems

Mixed Crop-Livestock

Agro Pastoral

Pastoral

Reasons

R1

R2

R3

I1

R1

R2

R3

I2

R1

R2

R3

I3

Overall I

Income

87

1

0

0.52

41

31

3

0.35

23

35

8

0.28

0.38

Meat

2

35

18

0.18

1

10

28

0.09

5

18

13

0.12

0.13

Milk

0

0

3

0.01

47

36

2

0.40

56

9

5

0.36

0.26

Saving

1

18

9

0.09

0

7

13

0.07

6

8

4

0.07

0.08

Wealth

0

24

18

0.13

1

5

22

0.06

0

7

24

0.07

0.09

Ceremony

0

4

6

0.03

0

0

11

0.02

0

3

18

0.05

0.03

Manure

0

3

14

0.04

0

0

0

0.00

0

0

0

0.00

0.01

Blood

0

0

0

0.00

0

0

0

0.00

0

9

2

0.04

0.04

Dowry

0

0

0

0.00

0

1

6

0.01

0

0

11

0.02

0.01

Tail fat

0

0

0

0.00

0

0

5

0.01

0

0

0

0.00

0.00

Total

90

85

68

1.00

90

89

90

1.00

90

89

85

1.00

1.00

R=Rank; I=Index; I= sum of [3 for rank 1+2 for rank 2 + 1 for rank 3] given for an individual reason divided by sum [ 3 for rank
1+2 for rank 2 + 1 for rank 3] for all reasons

Sheep acquisition and mode of disposal

Knowledge about ways of acquisition of breeding stock and mode of disposal is important in assessing the breeding practices of sheep owners. The major form
of sheep acquisition was birth (0.64) followed by gift (0.18) and purchase (0.15) (Table 2). Birth was the major form of sheep acquisition across all
production systems, though the index values varied. Sheep acquisition in the form of gift was ranked second in both agro-pastoral (0.26) and pastoral
(0.23) production systems; purchasing was ranked last (0.05 and 0.01, respectively) as found for goat in the same systems in Uganda (Jimmy et al 2012).

Table 2. Sheep acquisition methods in different livestock production systems in eastern Ethiopia

Acquisition methods

Mixed Crop-Livestock

Agro Pastoral

Pastoral

R1

R2

R3

I

R1

R2

R3

I

R1

R2

R3

I

Overall I

Birth

68

0

0

0.56

90

0

0

0.66

88

0

0

0.70

0.64

Purchase

22

36

0

0.38

0

10

0

0.05

0

2

0

0.01

0.15

Gift

0

6

6

0.05

0

54

0

0.26

0

44

0

0.23

0.18

Exchange

0

0

3

0.01

0

0

13

0.03

0

0

21

0.06

0.03

Total

90

42

9

1.00

90

64

13

1.00

88

46

21

1.00

1.00

R=Rank I=Index; I= sum of [3 for rank 1+2 for rank 2 + 1 for rank 3] given for an individual reason divided by sum [ 3 for rank 1+2 for
rank 2 + 1 for rank 3] for all reasons

The major mode of disposal was selling (0.47), followed by slaughtering (0.32) and death (0.08) (Table 3). The indices were consistent with each other
across all the production systems except for donation of sheep which had a much lower value in agro-pastoral (0.02) and pastoral (0.05) systems than in the
mixed crop-livestock system (0.13). Group discussion indicated that sheep disposal due to death in mixed crop-livestock (0.13) and pastoral (0.11) systems
might be associated with lack of veterinary services.

Table 3. Way of removal of sheep from the farm as ranked by respondents in different livestock production systems

Mixed Crop-Livestock

Agro Pastoral

Pastoral

Way of removal

R1

R2

R3

I

R1

R2

R3

I

R1

R2

R3

I

Overall I

Sold

67

2

0

0.4

90

0

0

0.52

74

11

2

0.47

0.47

Slaughter

0

62

9

0.26

0

90

0

0.34

16

57

0

0.28

0.32

Exchange

0

1

1

0.01

0

0

58

0.11

0

9

13

0.06

0.06

Donated

3

4

44

0.13

0

0

10

0.02

0

1

22

0.05

0.03

Death

18

6

7

0.14

0

0

2

0.01

0

11

23

0.11

0.08

Predator

0

15

5

0.07

0

0

7

0.01

0

0

17

0.03

0.04

Total

88

90

66

1.00

90

90

77

1.00

90

89

77

1.00

1.00

R=Rank I=Index; I= sum of [3 for rank 1+2 for rank 2 + 1 for rank 3] given for an individual reason divided by sum [ 3 for rank 1+2 for
rank 2 + 1 for rank 3] for all reasons

Sheep owners reported that rams were sold at an early age because of higher market demand across production systems; ewes were sold only if there was an
urgent need for cash income. Getting mature ram became difficult in all production systems but more serious in mixed crop-livestock production system
(field observation). The sale of ram lambs at an early age can have a negative effect on selection if preference is given to individuals that reach market
weight faster than those which are not sold (Getachew et al 2010). Hence, the issue of how to retain or obtain replacement stock, especially rams, needs
urgent attention for sustainable utilization of available resources and to improve overall productivity.

Breeding practices

Mating system and sources of breeding rams

Mating was predominantly uncontrolled in most of the production systems. However, controlled mating was practiced to some extent to match lambing time with
wet season and to avoid indiscriminate breeding in the pastoral production system. Methods of control included separating males from females at all times,
especially during dry season, and castration. Girma (1999) and Tilahun et al (2006) in the south-east lowlands and north-western of the Somali Region in
eastern Ethiopia respectively indicated that controlled breeding to capture both the desired selection criteria and to match lambing with the rainy season
enhances the survival rate of the offspring.

Out of the 90 respondants in each production system, 98%, 89% and 71% in the pastoral, agro-pastoral and mixed crop-livestock systems, respectively, kept
their own indgenous breeding rams. Those respondants with no breeding rams used those of neighbours or communal rams. In pastoral and agro-pastoral
production systems, sheep flocks under one ownership were generally not mixed with others; where communal flocks existed and mating takes place at random,
owners indicated that they were unable to identify the ram. The majority of breeding rams originated from within the flock in all production systems,
though some breeding rams were purchased from market in the mixed crop-livestock system. Group disscussion in mixed crop-livestock system indicated that
communal grazing land is being shifted into cultivated land and the households are forced to keep their sheep near homestead. Hence, the level of
inbreeding might be high in mixed crop-livestock system where commuinal grazing is becoming less and less important.

Assuming that mating was random and that flocks were not mixed, average inbreeding coefficients of 0.02, 0.03 and 0.16 were estimated for pastoral,
agro-pastoral and mixed crop-livestock systems, respectively. Thus the level of inbreeding was within the maximum acceptable level of 0.06 (Armstrong,
2006) in pastoral and agro pastoral production systems but higher in mixed crop-livestock system. While the level of inbreeding in pastoral and
agro-pastoral systems was minimal, utilization of breeding rams born within the flock and lack of awareness about inbreeding may lead to the accumulation
of problems associated with inbreeding and may decrease genetic diversity (Kosgey 2004), because the gene pool narrows (Edea et al 2012). In mixed
crop-livestock systems, relatively high inbreeding coefficient because of uncontrolled mating and absence of sharing communal land for communal herding
might potentially increase the risk unless appropriate measure is taken.

Inbreeding can be minimized by communal herding which allows breeding females to mix with males from other flock, the early castration of males related
with ewes in the same flock, and rotational use of breeding males (Jaitner et al 2001; Kosgey 2004). This was rarely practiced by farmers in the mixed
crop-livestock system. Controlled breeding requires strong extension services to ensure that rams are used efficiently to maximise the benefit (Edea et al
2012). Controlled breeding and matching the lambing season to coincide with the availability of fodder in the pastoral production system should be embraced
when initiating sustainable genetic improvement programs.

Selection criteria

The majority of the respondents selected potential breeding rams and ewes from within their herds, though selection of rams was more frequent than for ewes
as has been recorded previously in other districts of the SNRS (Ferew, 2008). In selecting a breeding ram, appearance (0.28) was ranked first, then fast
growth (0.23) and coat color (0.14). However, selection criteria and their index value differed among production systems.

In the crop-livestock mixed production system, appearance (0.35) was ranked first, then coat color (0.31) and fast growth (0.23) (Table 4). In the agro-
pastoral system, fast growth (0.26) was ranked first, then appearance (0.21) and coat color (0.11). Sheep owners reported that male sheep could be ready
for market at age six months if cash was needed urgently, though the normal selling time was between ages 1-to-2 years of age which fetch premium price.
The high attribute of fast growth of ram for breeding and meat production might due to high market demand and the proximity of the study area to export
market. In the pastoral production system, appearance (0.28) was ranked first, then age (0.20) and fast growth (0.19). Tail type (0.16), which indicates a
fat rump, is an important trait for selecting breeding rams; fat-rumped sheep are in high demand for religious festivals and export markets. Fat extracted
from the tail was also believed to have medicinal value to cure stomach illness and temporary sterility of women in both pastoral and agro-pastoral
production systems. Mbuku et al (2010) indicated use of fat deposition of sheep as selection criteria in northern parts of Kenya and pastoralists in that
area harvest fat from their sheep for home consumption.

Appearance of rams, which most of the owners associated with high carcass output and premium price across all the production systems, includes wide chest,
conformation and long body size. Gizaw et al (2010) has shown that the overall appearance of sheep is an important economic trait that influences value,
particularly in the traditional markets of Ethiopia. While coat color was an important selection criterion, its index varied with production system. Red,
white or mixed colors were more preferred in the mixed crop-livestock system, while a black head with a white body was preferred in agro-pastoral and
pastoral production systems. While black coat color mostly unwanted color due to less market value across all the production systems and pure white and red
head with white body are unwanted color in both agro-pastoral and pastoral production systems due to less resistance for drought and disease. Previous
reports noted that black coat color is generally less preferred color in most parts of Ethiopia (Ferew 2008; Edea et al 2012).

Greater emphasis was given in the pastoral production system to adaptive traits such as tail type (0.16) and adaptation to heat stress, feed scarcity and
disease resisitance (0.17) than in agro-pastoral and mixed crop-livestock systems. This might be due to the fact that respondents from pastoral production
system are coping with more challenging production environments as compared to the other production systems. Animals with good adaptive potential are
needed in these stressful environments to sustain the livelihoods of the communities (Gizaw et al 2010; Mirkana 2010). On the other hand, Edea et al (2012)
reported that adaptive traits such as tolerance to diseases and feed shortage were given low emphasis in selecting replacement stocks in mixed farming
system of western and south western parts of Ethiopia. Hence, trait for appearance, coat color and adaptation to stress should be considered besides
production traits in decision making to define breeding objectives of the sheep owners in all three production systems.

Table 4. Selection criteria for a breeding ram as ranked by respondents in different livestock production systems

In selecting a breeding ewe, appearance (0.46) was ranked first followed by coat color (0.17) and lamb survival (0.15) (Table 5). As with rams, the index
value differed between the production systems. In the mixed crop-livestock system, appearance (0.50) was ranked first followed by coat color (0.32) and
lamb growth (LG, 0.08). In the agro-pastoral production system, appearance (0.42) was ranked first followed by milk yield (0.18) and lamb survival (LS,
0.15). In the pastoral production system, appearance (0.42) was ranked first, then LS (0.26) and milk yield (0.18). Thus overall appearance based on body
conformation and size was the major selection criterion in all three systems. Higher milk yield, LS and LG were more important selection criteria in
pastoral and agro-pastoral systems than in the mixed crop-livestock system which were considered highly associated with mothering ability. Mothering
ability of ewes embraces maternal behavior that allows proper bonding to take place between mother and offspring, as well as nursing behavior,
responsiveness and attentiveness towards the lambs, and protection of the lambs from predators (Duguma et al 2011).

Table 5. Selection criteria for breeding ewe as ranked by respondents in different livestock production systems

In summary, across all the production systems, overall appearance was the most preferred attribute for selecting both breeding rams and breeding ewes. The
next most important were fast growth and coat color for rams and mothering ability for ewes. Thus, the current study indicated that more attention were
given to observable attributes like appearance, coat color and tail type compared to production and reproduction traits in selecting both breeding ram and
ewe across all the production systems. Mirkena (2010) has asserted that traditional breeders value both tangible and intangible traits; the latter are
often forgotten in conventional evaluation methods used to define breeding objectives which is particularly true in most genetic improvement programs
attempted in the tropics.

Conclusion

Different production objectives, breeding practices and selection criteria for selecting breeding stock exist among sheep production systems in eastern
Ethiopia. Based on purpose of keeping sheep, increasing meat production (improve growth rate and conformation) for crop-livestock mixed system and
increasing milk yield and meat production for pastoral and agro-pastoral system were found to be preferred traits in defining breeding objectives. Using
ram born from own farm and avoiding mixing of flock with others in both agro-pastoral and pastoral systems; and relatively high inbreeding coefficient
found in the mixed crop-livestock system suggests that action is needed to minimize the risk of inbreeding depression. Besides production trait, observable
attributes like appearance, coat color and some adaptive traits of breeding ram and ewe should be considered in decision making. Hence, these differences
in production objectives, trait preferences and breeding practices of sheep owners in the different production systems need to be considered in designing
sustainable breeding strategies for improved productivity in regions represented by the study area.

Acknowledgments

This study was sponsored by Haramaya University and Swedish International Development Agency (Sida) cooperation. We would like to thank BecA-ILRI Hub for
providing training on scientific research paper writing to the first author and Dr. Chris Beadle, CSIRO for his support during draft write up of the paper.

Tibbo M, Philipsson J and Ayalew W 2006
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